#include "LCommon.h"

BigNumber::BigNumber()
{
	_bn = BN_new();
	_array = NULL;
}

BigNumber::BigNumber(const BigNumber &bn)
{
	_bn = BN_dup(bn._bn);
	_array = NULL;
}

BigNumber::BigNumber(ui32 val)
{
	_bn = BN_new();
	BN_set_word(_bn, val);
	_array = NULL;
}

BigNumber::~BigNumber()
{
	BN_free(_bn);
	delete[] _array;
}

void BigNumber::SetDword(ui32 val)
{
	BN_set_word(_bn, val);
}

void BigNumber::SetQword(ui64 val)
{
	BN_add_word(_bn, (ui32)(val >> 32));
	BN_lshift(_bn, _bn, 32);
	BN_add_word(_bn, (ui32)(val & 0xFFFFFFFF));
}

void BigNumber::SetBinary(const ui8 *bytes, int len)
{
	ui8 t[1000];
	for (int i = 0; i < len; i++) t[i] = bytes[len - 1 - i];
	BN_bin2bn(t, len, _bn);
}

void BigNumber::SetHexStr(const char *str)
{
	BN_hex2bn(&_bn, str);
}

void BigNumber::SetRand(int numbits)
{
	BN_rand(_bn, numbits, 0, 1);
}


BigNumber BigNumber::operator=(const BigNumber &bn)
{
	BN_copy(_bn, bn._bn);
	return *this;
}

BigNumber BigNumber::operator+=(const BigNumber &bn)
{
	BN_add(_bn, _bn, bn._bn);
	return *this;
}

BigNumber BigNumber::operator-=(const BigNumber &bn)
{
	BN_sub(_bn, _bn, bn._bn);
	return *this;
}

BigNumber BigNumber::operator*=(const BigNumber &bn)
{
	BN_CTX *bnctx;

	bnctx = BN_CTX_new();
	BN_mul(_bn, _bn, bn._bn, bnctx);
	BN_CTX_free(bnctx);

	return *this;
}

BigNumber BigNumber::operator/=(const BigNumber &bn)
{
	BN_CTX *bnctx;

	bnctx = BN_CTX_new();
	BN_div(_bn, NULL, _bn, bn._bn, bnctx);
	BN_CTX_free(bnctx);

	return *this;
}

BigNumber BigNumber::operator%=(const BigNumber &bn)
{
	BN_CTX *bnctx;

	bnctx = BN_CTX_new();
	BN_mod(_bn, _bn, bn._bn, bnctx);
	BN_CTX_free(bnctx);

	return *this;
}

BigNumber BigNumber::Exp(const BigNumber &bn)
{
	BigNumber ret;
	BN_CTX *bnctx;

	bnctx = BN_CTX_new();
	BN_exp(ret._bn, _bn, bn._bn, bnctx);
	BN_CTX_free(bnctx);

	return ret;
}

BigNumber BigNumber::ModExp(const BigNumber &bn1, const BigNumber &bn2)
{
	BigNumber ret;
	BN_CTX *bnctx;

	bnctx = BN_CTX_new();
	BN_mod_exp(ret._bn, _bn, bn1._bn, bn2._bn, bnctx);
	BN_CTX_free(bnctx);

	return ret;
}

int BigNumber::GetNumBytes(void)
{
	return BN_num_bytes(_bn);
}

ui32 BigNumber::AsDword()
{
	return (ui32)BN_get_word(_bn);
}

ui8 *BigNumber::AsByteArray()
{
	if (_array) {
		delete[] _array;
		_array = NULL;
	}
	_array = new ui8[GetNumBytes()];
	BN_bn2bin(_bn, (unsigned char *)_array);

	std::reverse(_array, _array + GetNumBytes());

	return _array;
}

const char *BigNumber::AsHexStr()
{
	return BN_bn2hex(_bn);
}

const char *BigNumber::AsDecStr()
{
	return BN_bn2dec(_bn);
}